This invention relates generally to a projectile for the insertion of filling yarn into the warp shed of a loom wherein the filling yarn is supplied from a supply package located outside of the warp shed. The present invention is particularly directed to a projectile of the type in which at least a portion of a pick of the filling yarn is stored in a filling storage chamber within the projectile, and withdrawn therefrom during the projectile flight through the warp shed. This type of projectile and the loom in which it is used is shown in U.S. Pat. No. 3,831,640, issued to Karl W. Wueger, on Aug. 27, 1974. In the loom of this U.S. Patent, at least a portion of a pick of the filling is inserted into the projectile by means of an air flow which passes into one filling chamber and out of the other chamber, depositing yarn into the first filling chamber, prior to launching the projectile through the warp shed for inserting filling therein.
This invention is particularly directed to the class of projectiles in which at least a portion of the filling pick is inserted into the projectile by use of air currents. Projectiles of this type are designed to permit air to flow through the storage chamber from an inlet opening and to allow the filling yarn, entering through the inlet opening, to be carried by the air flow and be deposited within the chamber. The manner in which the filling is deposited in the chamber is critical for the withdrawal of the filling as the projectile passes through the warp shed. If the filling is deposited in a random, haphazard manner, snarls are likely to occur as the filling is withdrawn. In addition, it is important that the filling be withdrawn smoothly and evenly.
Another problem sometimes encountered is that the means which permits the air to flow through the chamber for depositing filling within the chamber also causes a reverse air flow during the projectile flight, thus causing the filling yarn stored in the chamber to be sometimes blown out of the trailing end of the projectile prematurely and thereby to deposit the filling in a bunch or snarl within the warp shed. This produces a defective pick and defective fabric.
Occasionally, difficulties have been encountered in loading the filling into the projectile. As the filling is deposited in the storage chamber it tends to settle against the outlet openings of the chamber and to block these openings thereby reducing the air flow through the projectile and interfering with the proper deposit of additional filling yarn into the projectile.
Many of the problems stated above have been overcome by the projectile developed by my co-worker, Petras Cyvas, and disclosed in U.S. patent application Ser. No. 960,344, filed Nov. 13, 1978, for "LOOM PROJECTILE". The projectile in this application has either one or two flat storage chambers located within a cylindrical body. A disadvantage of this type of projectile is that the storage chamber carrying filling is located completely on one side of the center of gravity of the projectile; therefore, the yarn causes an imbalance in the projectile.
Another disadvantage of this type of projectile is that the storage chambers utilize only a small portion of the entire cylindrical body cavity with a substantial amount of dead space between the inner wall of the cylindrical body and the outer walls of the storage chamber. This means that a projectile of a given diameter can carry less filling yarn than one of the structure of the instant invention.
Another disadvantage of the projectile disclosed in the above identified application, at least in the two-chamber version, is that the air currents carrying the yarn generally must change their direction of flow substantially 90 degrees in order to exit from the chamber after depositing the yarn therein.
It is a principal object of the present invention to provide a loom projectile which includes two filling storage chambers which extend across the center of gravity of the projectile in each instance and in which filling is deposited in a manner which permits the filling to be withdrawn evenly and smoothly from the projectile without causing snarls or twists therein.
Another object of the invention is the provision of a projectile for inserting filling into the warp shed of a loom in which the stored filling is evenly deposited within the projectile and which will not be blown out of the projectile prematurely by air currents passing through the projectile during the projectile's flight.
A further object of the present invention is the provision of a projectile for carrying filling to the warp shed of a loom which utilizes substantially the entire interior cavity of the projectile for storing filling yarn and which offers little or no interference to air currents flowing through the projectile, but does not let the filling be blown out prematurely thereby.